Doctor blade for rotogravure cylinder



Jan. 2, 1968 K.'A. KLINGLER 3,361,059

DOCTOR BLADE FOR RQTOGRAVURE CYLINDER o Sheet sSheet 1 Filed March 11, 1965 an), u, Ziw, MhFrzd affforziegs Jan. 2, 1968 K. A. KLINGLER 3, ,059 v DOCTOR BLADE FOR ROTOGRAVURE CYLINDER l0 Sheets-Sheet 2 Filed March 11, 1955 Jan. 2, 1968 K. A. KLINGLER DOCTOR BLADE FOR ROTOGRAVURE CYLINDER 1O Sheets-Sheet 5 Filed March 11, 1965 III II Jan. 2, 1968 K. A. KLiNGLER 3,361,059

DOCTOR BLADE FOR ROTOGRAVURE CYLINDER Filed March 11, 1965 10 Sheets-$heet 4 Jan. 2, 1968 K. A. KLINGLER 3,361,059

DOCTOR BLADE FOR ROTOGRAVURE CYLINDER 1Q Sheets-Sheet 5 Filed March 11, 1965 Jan. 2, 1968 K. A. KLINGLER DOCTOR BLADE FOR ROTOGRAVURE CYLINDER 1O Sheets-Sheet 6 Filed March 11, 1965 K. A. KLINGLER DOCTOR BLADE FOR ROTOGRAVURE CYLINDER Jan. 2, 1968 1,0 Sheets-Sheet '7 Filed March 11, 1965 Jan. 2, 1968 K. A. KLINGLER DOCTOR BLADE FOR ROTOGRAVURE CYLINDER Filed March 11, 1965 1,0 Sheets-Sheet 8 Jan. 2, 1968 K. A. KLINGLER DOCTOR BLADE FOR ROTOGRAVURE CYLINDER 1O Sheets-Sheet 9 Filed March 11, 1965 Jan. 2, 1968 K. A. KLINGLER 3,351,059

DOCTOR BLADE FOR ROTOGRAVURE CYLINDER Filed March 11, 1965 10 Sheets-Sheet 1O FIE-14 United States Patent ware Filed Mar. 11, 1965, Ser. No. 438,928 15 Claims. (Cl. 101169) This invention relates to rotogravure printing machines, and in parti ular it relates to a novel mounting for the doctor blade of a rotogravure printing machine.

In rotogravure printing a rotogravure cylinder having an intaglio printing surface rotates with its lower portion in an ink reservoir, and a doctor blade contacts the cylinder surface to remove all ink from the areas between the ink bearing recesses of the cylinder. The doctor blade is mounted for reciprocal movement in an axis generally parallel to the cylinder axis so that uneven doctoring of the cylinder due to imperfections in the blade, or foreign matter on the blade, will be wiped out by the reciprocation of the blade. The practical impossibility of machining a precisely cylindrical object requires that the doctor blade be mounted for angular movement to follow the cylinder surface. Such mountings as heretofore used have included a pair of mounting devices adjacent opposite ends of the blade, and have not permitted the blade to follow the cylinder surface accurately. Where a plurality of mountings are secured at spaced locations along the blade, each tends to limit the other with respect to movement of the blade relative to the cylinder. Such a mounting would require a very complex linkage to permit the blade to be completely self-aligning and thus remain in uniform contact with the rotating cylinder.

The principal object of this invention, therefore, is to provide a new and improved mounting system for mounting a doctor blade in association with a rotogravure cylinder.

A further object is to provide such a system which comprises only a single mounting device.

Still another object is to provide a doctor blade mounting that includes a single swivel head which permits universal movement of the blade to follow the cylinder surface.

A further object is to provide a new and useful doctor blade mounting system which permits limited movement of the blade in a plurality of directions relative to the rotogravure cylinder axis while in engagement with the cylinder surface for following the surface and to provide a new and useful arrangement for limiting such movement within adjustable bounds.

Yet another object is to provide a system in which the doctor blade may be positively urged against the cylinder surface under preset pressure.

And another object is to provide a mounting which permits compound pivotal movement of a doctor blade which is being reciprocated axially relative to the cylinder surface.

Commonly doctor blades are mounted so as to form an acute angle relative to the cylinder surface as it approaches the blade. A so-called reverse doctor blade is mounted to form an obtuse angle relative to the approaching cylinder surface, and such reverse mounted blades require very delicate adjustment of blade pressure on the cylinder to avoid damage to the cylinder surface. They have rarely been used because correct blade pressure adjustment is very hard to achieve.

One form of the present invention is particularly designed to permit very fine and accurate adjustment of reverse mounted doctor blade disposition and pressure on the cylinder surface, so as to permit use of a reverse 3,361,059 Patented. Jan. 2, 1968 ice blade, which can often doctor the cylinder surface more cleanly than can a conventionally mounted blade.

Other objects will be apparent from the following description and the drawings in which:

FIG. 1 is a fragmentary perspective view of a rotogravure printing machine showing a first form of my novel doctor blade mounting;

FIG. 1A is a diagrammatic view of the first form of the doctor blade mounting;

FIG. 2 is an end view of the first form of doctor blade mounting viewing F IG. 1 from the left end;

FIG. 3 is a fragmentary section generally along the line 3-3 of FIG. 2 with parts broken away;

FIG. 4 is an enlarged fragmentary section along the line 44 of FIG. 3;

FIG. 5 is a greatly enlarged fragmentary section of the doctor blade shown in the system of FIGS. 1-4-;

FIG. 6 is a fragmentary section along the line 6-6 of FIG. 4;

FIG. 7 is a fragmentary section along the line 7-7 of FIG. 6;

FIG. 8 is a fragmentary section along the line 3--8 of FIG. 7;

FIG. 9 is a fragmentary elevational view along the line 99 of FIG. 4;

FIG. 10 is a fragmentary section along the line Ill-10 in FIGS. 4 and 9;

FIG. 11 is a fragmentary section along the line 11-11 of FIG. 4;

FIG. 12 is a diagrammatic illustration of an air supply and control system for actuating fluid pressure responsive cylinders suitable for use in the system of FIGS. 1-11;

FIG. 13 is a section similar to FIG. 4, but through a second form of my novel doctor blade mounting; and

FIG. 14 is a fragmentary section along the line 13-13 in FIG. 12.

While this invention is susceptible of embodiment in many different forms, there is shown in the drawings and will herein be described in detail two specific forms of the invention with the understanding that the present disclosure is to be considered as an exemplification of the principles of the invention and is not intended to limit the invention to the forms illustrated.

Referring to the drawings in greater detail, and first referring to FIGS. 1, 1A and 2, a rotogravure cylinder 21 is mounted for counterclockwise rotation partially in an ink fountain 22, in the usual way; and a doctor blade 23 removes ink from the cylinder 21 in the usual manner of a reverse doctor blade so that a clean impression is made on a paper web which passes between the cylinder 21 and an impression cylinder 24. The present invention is directed to the apparatus that mounts the doctor blade for adjustment and floating movement relative to the cylinder 21.

The structure illustrated in FIGS. 1 through 11 has a reverse doctor blade 23 which is mounted at an obtuse angle with respect to the approaching surface of the rotating cylinder 21 (see FIG. 2). Blade 23 is held in position by a blade holder or clamp, indicated generally at 25, which is centrally supported by a single swivel head assembly, indicated generally at 26; and hydraulic motor means, indicated generally at 27, is provided for moving the swivel head assembly and blade 23 toward and away from rotogravure cylinder 21; the entire structure being carried by a frame assembly, indicated generally at 30.

As best seen in FIG. 5, the reverse doctor blade 23 includes a surface 23a that tapers to a thin scraping edge 23b which contacts the surface of cylinder 21 with surface 23a facing the cylinder. Referring to FIG. 2, it will be noticed that blade 23 is mounted to ride on the surface of cylinder 21 very close to the nip between cylinder 21 and roll 24 to minimize drying of the ink between the blade 23 and the nip, where the rotogravure cylinder contacts the paper web.

Referring especially to FIGS. 1-3, the frame assembly 30 is secured to a conventional slider plate 28 which makes a sliding dovetail connection with a slide mounting plate 29 that is secured to a back plate 22a of reservoir 22; and a conventional reciprocating drive (not shown) reciprocates the slider 28 in the usual way to reciprocate the doctor blade lengthwise of the cylinder.

The frame assembly 30 includes a bracket member 32 that is secured to slider plate 28 and has parallel outer arms 32a and inner plates 32b. As best seen in FIGS. 1 to 4, aligned pivot pins 35 are mounted in the outer arms 32a and the lower portions of the inner plates 32b, and an Aframe 33 has spaced legs provided with hollow bearing bosses 33a and roller bearings 37 by which said A- frame is journaled on the pins 35. In the upper portions of plates 3212 are pins 36 that pivotally mount a pair of rocker arms 34. The rocker arms have inwardly extending, aligned journal plugs 38 having bores 39 in which pins 41 of a cylinder mounting trunnion 42 are journaled. A motor in the form of a two direction hydraulic cylinder 43 is clamped in trunnion 42 and has a downwardly extending piston rod 44 with a bifurcated end 45 pivotally secured by a pin 46 to a lug 47 that is integral with bracket 32; so that extension of the piston rod 44 pivots the rocker arms 34 from the full line position of FIG. 2 to the broken line position of FIG. 2.

Referring now to FIGS. 1 to 4 and 6, rocker arms 34 and A-frarne 33 are provided with bores 48 and 49, respectively, pivotally receiving shafts 52 and 53, respectively, which extend, respectively, between the rocker arms 34 and the legs of A-frame 33 and are constrained against axial movement.

A pair of lost motion links 54 which are between the rocker arms have bores 54a by which they are pivotally hung from shaft 52, and have oversized bores 54b (FIG. 4) at their lower ends to make lost motion connections with the shaft 53 and thus permit limited relative motion between the outer end of the A-frame 33 and the rocker arms 34. The ends of the shaft 52 and 53 project beyond the rocker arms and the A-frame legs and have holes to receive threaded studs 55a and 55b by which coil springs 55 are adjustably tensioned between the shafts by the use of adjusting nuts 56, so the shaft 53 is biased toward the shaft 52 within the limits of bores 5412. Also biasing between shafts 52 and 53 is a motor in the form of a one-way air cylinder 57 which is secured to shaft 52 and has a piston rod 58 secured to shaft 53, so that extension of piston rod 58 overcomes springs 55 to drive shaft 53 away from shaft 52 within the limits of the bores 5419. Upon release of air from cylinder 57 the springs 55 cause piston rod 58 to retract and return shaft 53 toward shaft 52.

It will be noted that as cylinder 43 is actuated to pivot rocker arms 34 clockwise as viewed in FIG. 2, links 54 and springs 55 lift shaft 53 to pivot A-frame 33 clockwise about pins 35 and thus raise A-frame 33 to the broken line position of FIG. 2. The loose fit of link 54 functions to limit the relative movement between rocker arms 34 and A-frame 33.

After reversing hydraulic cylinder 43 to return rocker arms 34 and A-frame 33 to the position shown in full lines, the combination of springs 55 and air cylinder 57 provides a fine adjustment of the disposition of A-frarne 33 relative to rocker arms 34 for purposes which will be described hereinbelow. An adjustable stop screw 59 (FIG. 4) is provided to limit the downward travel of each link 54, and therefore also limit the downward pivotal movement of A-frame 33 and rocker arms 34 by hydraulic cylinder 43.

Referring to FIGS. 3 and 4, the single swivel head 26 is carried by the outer end of A-frame 33 and permits swivelling of the doctor blade holder 25 toward the roller and in two planes relative to the roller. Accordingly, a pair of aligned, hollow bearing bosses 61 in A-frame 33 carry roller bearings 62 to receive stub pivots 63 of a trunnion housing 64 which has opposite planar side faces that abut circular inwardly facing ends of the bearing bosses 61 and are provided with O-rings 65a and 6512 which seal against the ends of said bearing bosses. Thus, trunnion housing 64 may pivot clockwise or counterclockwise relative to A-frame 33 as viewed in FIG. 2. The ends of bearing bosses 61 are provided with closures 61a.

A shaft 66 is journaled in bearings 67 and 6711 within trunnion housing 64 and projects from one end of said trunnion housing to receive a journal box 68 which has a pair of parallel, generally upstanding brackets 69 bolted thereto and has a side closed by a cover plate 68a.

Referring to FIGURES 3, 4 and 10, a shaft 72 1s journaled in bearings '73 within journal box 68 and extends out of the journal box toward the cylinder 21 to receive a doctor head plate 74 to which blade clamp 25 is secured by bolts 75.

As best seen in FIGS. 4 and 9 to 11, blade clamp 25 includes clamp halves 76 and '77 secured together by bolts 78 and clamping doctor blade 23 therebetwcen in proper disposition for riding as a reverse doctor blade on cylinder 21. During riding of the doctor blade, shaft 72 (FIG. 4) permits clockwise and counterclockwise (as viewed in FIG. 3) pivoting of the blade holder and blade, while shaft 66 permits pivoting of the blade in a plane perpendicular to the plane of the paper viewed in FIG. 3. In each case, the pivoting movement of the blade permits the ends of the blade to move toward and away from the cylinder, but in two different planes.

Referring to FIGS. 1, 2, 4, 9 and 10, head plate 74 has a planar surface 74a which is in close, generally parallel association with a stop member 79, secured by bolts 82 which impale slots 83 and screw into housing 64. Bolts 82 may be loosened and stop member 79 may be adjusted toward and away from surface 74a to provide a proper gap 84 for stopping pivoting of blade 23 on the axis of shaft 72 by abutment with surface 74a at the maximum desired permissible amount of such pivoting.

In operation of the device, nuts 56 are p-re-adjusted to provide a desired or preselected amount of tension of springs 55, biasing shafts 52 and 53 together and biasing air cylinder 57 against extension of the piston rod 58, so that with air cylinder 43 contracted and swivel head 26 in its down position, extension of piston rod 58 causes shaft 53 to move away from shaft 52 within the limits of bores 54b to force A-frame 33 downward, resulting in application of the precise desired amount of pressure of blade 23 on cylinder 21. The tension of springs 55 determines inversely the amount of blade pressure and the adjustability of spring tension can permit very fine adjustment of blade pressure within the useful range of blade pressure. Excessive blade pressure applied to a reverse doctor blade can result in cutting the rotogravure cylinder surface due to the blade angle.

As best seen in FIGS. 2 and 4, a resilient splash plate 85 is supported by a mounting block 86 on ink reservoir 22. A replaceable wear pad 87 is secured along one edge of splash plate 85 to abut member 76 of blade clamp 25, since the splash plate is fixed and the blade clamp reciprocates longitudinally. Splash plate 85 causes ink removed from the cylinder 21 by the doctor blade to return to reservoir 22.

From the description of the trunnion 64 it is apparent that the swivel head assembly 26 must be adjustably connected to the A-frame 33 to prevent the doctor head plate 74 and doctor blade from pivoting loosely on the trunnion pivots 63. Such a connection is provided by adjustable connecting means, best seen in FIGS. 6 to 8, that include a pivot pin 88 in the brackets 69 that are on the journal box 68, a cross pin 89 that is carried between lugs 90 on the A-frame, and a threaded rod '91 which extends through a bore in pivot pin 88 and is secured by adjusting nuts 92. At the lower end of rod 91 is an integral bearing assembly, indicated generally at 93, which is impaled by cross pin 89 and includes an annular bearing housing 94, a bearing liner 95 which is fixed in the housing and has a spherical inner surface, and an annular bearing insert 96 which is rotatable about the cross pin 89 and has an outer surface complementary to the liner 95 so that the insert is universally rotatable in the liner. Thus, the threaded rod 91 and nuts 92 permit adjustment of the angular disposition of trunnion 64 on the A-frame, while the bearing assembly 93 permits slight pivotal movement of housing 63 and shaft 66 relative to housing 64, so as to limit the angular movement of the doctor blade about the axis provided by said shaft. The unit of rod 91 and integral bearing assembly 93 is commercially available under the trademark Rexlon.

Turning now to FIG. 12, suitable control circuitry is provided for actuating hydraulic cylinder 43 and the air cylinder 57 of the system of FIGS. 1 to 11. A high pressure air supply 102 connects with the usual press room high pressure air source (not shown). The air supply is divided between lines 102a and 1112b for operating the hydraulic cylinder 43 and the air cylinder 57, respectively, and is conducted through pressure regulating valves 103 and 104 to manually operable control valves 105 and 106, respectively. Control valve 105 is a four-way valve which is capable of shunting air from inlet 105a to either of outlets 10519 or 1050 while shunting the other of outlets 10512 or 1050 to exhaust 105d or 105e respectively. Depending on the position of valve 105, air is directed to one end or the other of an air cylinder 107 for either extending or retracting a piston rod 108 which is connected directly to a piston rod 109 of a piston 109a of a master hydraulic cylinder 110, with respect to which the hydraulic cylinder 43 is in a slave relationship in a closed loop hydraulic circuit that is provided with manually adjustable flow control valves 111 and 112. Thus, extension of the air cylinder piston rod 108 moves the master hydraulic cylinder piston 109a to force fluid outwardly through the flow control valve 111 and extend the piston rod 44, while at the same time fluid is returned through the flow control valve 112 to the cylinder 110 behind piston 109a. Conversely, retraction of air cylinder piston rod 108 moves piston 109a to force fluid outwardly through fiow control valve 112 and returns it through 111, thus retracting the piston rod 44. The master cylinder 110 is of larger capacity than the slave cylinder 43 so as to offset leakage which is inherent in a closed loop hydraulic circuit; and a small fluid reservoir 113 is in direct communication with both ends of the hydraulic cylinder 110 to make up fluid loss.

Air cylinder 57 is supplied with air for extending piston rod 58 by moving two-way manual control valve 106 to permit air flow from an inlet port 106a through a pressure port to a manually adjustable flow control valve 114 which regulates the rate of air flow to cylinder 57 and the rate of extension of piston rod 58. When valve 106 is moved to close inlet port 106a and place the pressure port 10611 in communication with an exhaust port 1060, the springs 55 retract the piston rod 58.

The operating characteristics of hydraulic cylinders make it more desirable to use such a cylinder to raise and lower the A-frame, rather than using an air cylinder for that purpose; and the use of the available press room high pressure air system to operate the master cylinder 110 eliminates the need for the hydraulic pump and reservoir ordinarily required for a hydraulic system. However, a conventional hydraulic system or a Wholly air system could be used.

An alternate doctor blade mounting system is shown in FIGS. 13 and 14, wherein all elements which are functionally similar to those in FIGS. 1 to 11 are given the same reference numeral, but 100 numbers higher; while dissimilar elements are given new numbers.

In the system of FIGS. 13 and 14, blade 123 is a conventional doctor blade and does not require the delicate final adjustment relative to cylinder 121 as used with the reverse doctor blade 23 because the conventional blade is at an angle relative to cylinder 121 such that it cannot cut the surface of cylinder 121 even if the blade pressure against the surface is excessive; therefore the rocker arms 34, springs 55, air cylinder 57, links 54 and associated elements of the delicate adjustment system of the device of FIGS. l-12 are eliminated and A-frame 133 is locked down onto pads 13317 secured to a slider plate 123 which makes a dovetail connection with plate 129 secured to fountain 122. Swivel head 126 is identical to swivel head 26 but all pivotal motion of swivel head 126 is around pivots 163 in bearing bosses 161. Thus, to move swivel head 126 a two-directional hydraulic cylinder 143 is mounted by a trunnion mounting 142 which extends be tween the lower portions of inner bracket plates 13212 of bracket member 132, with journal plugs 138 pivotally receiving trunnion pins 141; and the end of piston rod 144 of cylinder 143 is threadedly engaged with and carries female threaded connector 144a which is integral through a rod 191 with a bearing assembly 193, identical to hearing assembly 93 described above. Bearing assembly 193 is impaled by cross-pin 189 held by bracket 169, and is universally movable relative to cross-pin 189 to permit limited pivotal movement of housing 163 relative to housing 164. The threaded piston rod 144 and connector 144a permit adjustment of the angular disposition of swivel head 126 about pivots 163 to provide proper running contact pressure of blade 123 on cylinder 121 while blade 123 and swivel head 126 are in their working position as shown in full lines in FIG. 13.

The conventional doctor blade 123 is mounted by a mounting clamp which is constructed to hold blade 123 by clamp halves 176 and 177 on an acute angle to the approaching cylinder 121. The clamp 125 is secured to a doctor head plate 174 which is centrally supported by the swivel head 126 in the same manner head plate 24 is centrally supported by swivel head 26 in FIGS. 3, 4 and 10.

As previously described with reference to the first form of the invention, doctor head plate 174 has a surface 174a with which a stop member 179 is adjustably related by the same means heretofore described for said first form; so pivoting of blade 123 on the axis of housing 168 is limited.

To move swivel head 126 and blade 123 from working position to storage position (shown in phantom in FIG. 13), hydraulic pressure is applied from a suitable source to the upper end of cylinder 143 to retract or drive piston rod 144 downward as viewed in FIG. 13, pivoting swivel head 126 clockwise on pivots 163 as cylinder 143 also pivots on the axis of trunnion pins 141. To return the swivel head and blade to working position, hydraulic pressure to cylinder 14-3 is reversed and. piston rod 144 is extended to pivot swivel head 126 counterclockwise on pivots 163 so that blade 123 is carried into proper running contact with cylinder 121 as hydraulic cylinder 1 3 returns on the axis of pins 141, and clamp half 1'76 engages a splash plate which is secured by block 136 to the fountain 122. It will be noted that the hydraulic cylinder 143 has a much longer stroke than cylinder 1-3, but is otherwise similar and can be part of an air driven hydraulic system similar to that shown in FIG. 12.

I claim:

1. In a rotogravure printing machine having a rotogravure cylinder and a doctor blade, doctor blade mounting means comprising, in combination: a supporting frame and single swivel head means mounted on said frame, said swivel head means including a plurality of pivot members on separate axes, one of which is transverse to the axis of rotation of the cylinder, said pivot members supporting said blade for compound movement against the rotating cylinder surface for following the cylinder surface, at least one of said pivot members being freely pivoted on said transverse axis.

2. The machine of claim 1 wherein said supporting frame includes means defining a pivot joint between said head and a fixed part of the printing machine on an axis parallel to the cylinder axis, and means for moving said head and the blade supported thereon selectively between an operative position with the blade in contact with the cylinder surface and an inoperative position with the blade out of contact with the cylinder surface respectively.

3. In a rotogravure printing machine having a rotogravure cylinder and a doctor blade, in combination: means mounting said blade for pivotal movement on a plurality of axes one of which is parallel to the rotogravure cylinder surface and another of which is transverse thereto, so the blade follows the rotogravure cylinder surface, said mounting means including a member freely pivotal on said transverse axis, and adjustable means for limiting movement on each of said axes to a selected small angle of movement.

4. The machine of claim 3 including means supporting said mounting means for pivotal movement to carry said blade selectively into contact with or away from contact with said surface.

5. In a rotogravure printing machine having a rotogravure cylinder and a doctor blade, doctor blade mounting means comprising: a supporting frame, single swivel head means mounted on said frame and mounting said blade generally centrally on a first swivel axis which is parallel to the axis of rotation of the cylinder, said swivel head means including a plurality of pivots one of which is parallel to said swivel axis and one of which is transverse thereto, whereby the swivel head has compound movement about a plurality of additional axes for following the cylinder surface with said blade, said swivel head means including a blade holding member freely pivotal on said transverse axis; first selectively operable motor means acting on said mounting means for moving said blade between positions toward and away from the cylinder surface for engagement with and disengagement from said surface respectively; and second selectively operable motor means acting on said mounting means for pressing said blade into firm scraping contact with the cylinder surface.

6. The apparatus of claim 5 including adjustable stop means for stopping movement of the blade in the position toward the cylinder surface.

'7. The apparatus of claim 5 wherein said pressing means comprises an air cylinder for urging said blade against the rotogravure cylinder surface and tension spring means counteracting said air cylinder for urging said blade away from the rotogravure cylinder surface and including adjusting means comprising means for adjusting the tension of said spring means relative to the pressure of said air cylinder for setting the pressure of said blade against the rotogravure cylinder surface.

8. In a rotogravure printing machine having a rotogravure cylinder and a doctor blade, doctor blade mounting means comprising, in combination, a supporting frame, means mounting said blade on said frame for movement on a plurality of axes one of which is parallel to the cylinder axis, and another of which is transverse thereto, whereby the blade follows the rotogravure cylinder surface, said mounting means including a member freely pivotal on said transverse axis, and adjustable pressure means for urging said blade against the rotogravure cylinder surface under a preset pressure with said blade following the surface.

9. The apparatus of claim 8 wherein said mounting means includes means holding said blade at an obtuse angle relative to the approaching cylinder surface during following.

10. In a rotogravure printing machine having a rotogravure cylinder and a doctor blade, in combination: support means, a first arm pivotally mounted on said support means; blade holding means at the free end of said first arm; a second arm pivotally mounted on said support means at a position above and in generally parallel relationship to said first arm; lost motion means interconnecting the free ends of the first and second arms for conjoint pivotal movement of said arms with slight pivotal movement of the first arm toward and away from the second arm; tension means biasing the first arm toward the second arm; first motor means for pivotally moving said arms conjointly between a storage position with the blade remote from the cylinder and a ready position with the blade close to the cylinder surface; adjustable stop means for stopping said second arm, holding means and blade at said ready position, and second motor means for overpowering said tension means and pivotally moving said first arm slightly away from the second arm from ready position to a working position with the blade pressed against the cylinder surface.

II. In a rotogravure printing machine having a rotogravure cylinder and a doctor blade, doctor blade mounting means comprising in combination: a supporting frame, an arm pivotally mounted at one end on the frame on a first axis parallel to the axis of cylinder rotation, swivel head means pivotably mounted on the free end of said arm on a second axis parallel to the axis of cylinder rotation, means mounting said doctor blade on said swivel head, said swivel head including pivot members defining third and fourth axes for compound movement of the blade relative to said arm and relative to each of said first and second axes, and means for adjusting the angle of said swivel head relative to said arm on said second aXlS.

12. In a rotogravure printing machine having a rotogravure cylinder and a doctor blade, doctor blade mounting means comprising, in combination: a supporting frame, an arm pivotally mounted on the frame on a first axis parallel to the axis of cylinder rotation, swivel head means pivoted on the free end of said arm on a second axis parallel to the axis of cylinder rotation, means mounting said doctor blade on said swivel head, said swivel head including pivot members defining third and fourth axes for giving compound movement to the blade relative to said arm and relative to each of said first and second axes, selectively operable motor means for moving said swivel head on said first axis and adjustable means associated with said motor means for limiting blade movement on said third and fourth axes and for adjusting the blade pressure against the rotogravure cylinder surface.

13. In a rotogravure printing machine having a rotogravure cylinder and a doctor blade, doctor blade mounting means comprising in combination: a supporting frame, swivel head means carrying said blade for compound pivotal movement of said blade about a plurality of axes one of which is parallel to the cylinder axis and another of which is transverse thereto, said swivel head means including a member freely pivotal on said transverse axis, means mounting said swivel head for movement about an axis parallel to the axis of the cylinder, and motor means for moving said swivel head on said axis to bring the blade in and out of contact with the cylinder.

14. In a rotogravure printing machine having a rotogravure cylinder and a doctor blade, doctor blade mounting means comprising in combination: a supporting frame, swivel head means mounted on said frame, said swivel head means including a plurality of pivot members and supporting said blade for compound movement against the rotating cylinder surface for following the cylinder surface, and adjustable limiting means for limiting the pivoting in said swivel head means about one of said pivot members, said adjustable limiting means including an eyelet having an integral rod secured to one of said swivel head and frame, a pin generally coaxially impaling said eyelet and secured to the other of said swivel head and frame on an axis generally parallel to the axis of rotation of said cylinder, and universal bearing means for permitting limited relative universal movement between said eyelet and pin.

115. In a rotogravure printing machine having a rotogravure cylinder and a doctor blade, doctor blade mounting means comprising, in combination, a supporting frame, means mounting said blade on said frame for movement on a plurality of axes for following the rotogravure cy1- inder surface, adjustable pressure means for urging said blade against the rotogravure cylinder surface under a preset pressure with said blade following said surface, said adjustable pressure means comprising limiting lost motion means in said mounting means, means for applying a predetermined, generally constant pressure to said counteracting said pressure applying means, and means for adjusting the counteracting pressure of said counteracting means.

References Cited ROBERT E. PULFREY, Primary Exai'niner.

WILLIAM F. MCCARTHY, IR., Examiner.

blade Within limits of said lost motion means, means for 15 H. DINITZ, Assistant Examiner. 

1. IN A ROTOGRAVURE PRINTING MACHINE HAVING A ROTOGRAVURE CYLINDER AND A DOCTOR BLADE, DOCTOR BLADE MOUNTING MEANS COMPRISING, IN COMBINATION: A SUPPORTING FRAME AND SINGLE SWIVEL HEAD MEANS MOUNTED ON SAID FRAME, SAID SWIVEL HEAD MEANS INCLUDING A PLURALITY OF PIVOT MEMBERS ON SEPARATE AXES, ONE OF WHICH IS TRANSVERSE TO THE AXIS OF ROTATION OF THE CYLINDER, SAID PIVOT MEMBERS SUPPORTING SAID BLADE FOR COMPOUND MOVEMENT AGAINST THE ROTATING CYLINDER SURFACE FOR FOLLOWING THE CYLINDER SURFACE, AT LEAST ONE OF SAID PIVOT MEMBERS BEING FREELY PIVOTED ON SAID TRANSVERSE AXIS. 